| Noun | 1. | coagulation factor - any of the factors in the blood whose actions are essential for blood coagulationfactor I, fibrinogen - a protein present in blood plasma; converts to fibrin when blood clots factor X, prothrombinase - coagulation factor that is converted to an enzyme that converts prothrombin to thrombin in a reaction that depends on calcium ions and other coagulation factors factor XII, Hageman factor - coagulation factor whose deficiency results in prolongation of clotting time of venous blood factor XIII, fibrinase - in the clotting of blood thrombin catalyzes factor XIII into its active form (fibrinase) which causes fibrin to form a stable clot | |